The IRAK4 Knockout HAP1 Polyclonal Cells are a CRISPR/Cas9-edited polyclonal knockout cell population designed to eliminate functional IRAK4 expression in the HAP1 near-haploid human cell line. This product consists of a heterogeneous pool of cells carrying gene-disrupting modifications introduced by CRISPR/Cas9, enabling loss-of-function studies without clonal isolation. The polyclonal format retains population-level complexity while providing a robust model for investigating IRAK4-dependent processes.
The host HAP1 cell line, derived from the KBM-7 chronic myeloid leukemia lineage, is an adherent near-haploid human cell line widely employed in functional genomics and knockout screening. Its haploid karyotype simplifies genetic manipulation and reduces the likelihood of functional compensation by wild-type alleles, making it particularly suitable for CRISPR-based knockout studies. HAP1 cells retain key signaling pathways relevant to innate immunity and hematological contexts, providing a biologically meaningful background for functional studies of IRAK4.
IRAK4 is a serine/threonine kinase essential for innate immune signaling via Toll-like receptors (TLRs) and interleukin-1 receptors (IL-1Rs). It is recruited to MyD88 upon receptor activation and forms the Myddosome complex with IRAK1 and IRAK2, where it phosphorylates IRAK1. This initiates a cascade involving TRAF6, TAK1, and the IKK complex, activating NF-??B and MAP kinases (ERK, JNK, p38) which drive pro-inflammatory cytokine expression. IRAK4 also interacts with Pellino-1 and Pellino-2, which modulate signaling output. Thus, IRAK4 functions as a central kinase bridging receptor activation to transcriptional responses.
In HAP1 cells, IRAK4 disruption blocks TLR/IL-1R-mediated NF-??B and MAPK activation, creating a clean loss-of-function model. This is valuable for studying innate immune signaling, validating IRAK4 as a therapeutic target in autoimmunity and inflammation, and modeling IRAK4 deficiency. The chronic myeloid leukemia origin of HAP1 also makes it relevant for investigating innate immune roles in hematological malignancies.
Applications include Western blotting to confirm IRAK4 loss, RT-qPCR, phospho-signaling analysis (p-IRAK1, p-p65, p-JNK), NF-??B reporter assays, and cytokine ELISAs (IL-6, TNF-??) after TLR/IL-1R stimulation. The model is suitable for drug sensitivity tests with IRAK4 inhibitors, synthetic lethality screens, and RNA-seq transcriptome profiling. For further information or technical assistance, please contact Ascent Research.
